from django.shortcuts import render
from django.views.generic.base import View
from pure_pagination import Paginator, EmptyPage, PageNotAnInteger
from django.http import HttpResponse
from django.db.models import Q

import json

from .models import Course, CourseResource, Video
from operation.models import UserFavorite, CourseConments, UserCourse
from utils.mixin_utils import LoginRequiredMixin
# Create your views here.


class CourseListView(View):
    """
    课程列表页
    """
    def get(self, request):
        all_courses = Course.objects.all().order_by('-add_time')

        # 课程搜索
        search_keywords = request.GET.get('keywords', '')
        if search_keywords:
            all_courses = all_courses.filter(Q(name__icontains=search_keywords) |
                                             Q(desc__icontains=search_keywords) |
                                             Q(detail__icontains=search_keywords))

        # 热门推荐课程
        hot_courses = Course.objects.all().order_by('-click_nums')[:3]

        # 对公开课的排序
        sort = request.GET.get('sort', '')
        if sort:
            if sort == 'students':
                all_courses = all_courses.order_by('-students')
            elif sort == 'hot':
                all_courses = all_courses.order_by('-click_nums')

        # 对公开课进行分页
        try:
            page = request.GET.get('page', 1)
        except PageNotAnInteger:
            page = 1

        p = Paginator(all_courses, 3, request=request)

        courses = p.page(page)
        return render(request, 'course-list.html', {
            'all_courses': courses,
            'sort': sort,
            'hot_courses': hot_courses
        })


class CourseDetailView(View):
    """
    课程详情页
    """
    def get(self, request, course_id):
        course = Course.objects.get(id=int(course_id))

        # 增加课程点击数
        course.click_nums += 1
        course.save()

        has_fav_course = False
        has_fav_org = False

        if request.user.is_authenticated:
            if UserFavorite.objects.filter(user=request.user, fav_id=course.id, fav_type=1):
                has_fav_course = True

            if UserFavorite.objects.filter(user=request.user, fav_id=course.course_org.id, fav_type=2):
                has_fav_org = True

        # 相关课程推荐
        tag = course.tag
        if tag:
            relate_courses = Course.objects.filter(tag=tag)[:1]
        else:
            relate_courses = []

        return render(request, 'course-detail.html', {
            'course': course,
            'relate_courses': relate_courses,
            'has_fav_course': has_fav_course,
            'has_fav_org': has_fav_org
        })


class CourseInfoView(LoginRequiredMixin, View):
    """
    课程章节信息
    """
    def get(self, request, course_id):
        course = Course.objects.get(id=course_id)

        # 用户在课程详情页点击我要学习后，进去课程信息页，该课程学习人数增加
        course.students += 1
        course.save()

        # 查询用户是否已经关联该课程
        user_courses = UserCourse.objects.filter(user=request.user, course=course)
        if not user_courses:
            user_course = UserCourse(user=request.user, course=course)
            user_course.save()

        # 相关课程推荐
        user_courses = UserCourse.objects.filter(course=course)
        user_ids = [user_course.user.id for user_course in user_courses]
        all_user_courses = UserCourse.objects.filter(user_id__in=user_ids)
        # 取出所有课程 id
        course_ids = [user_course.course.id for user_course in all_user_courses]
        # 获取学过该课程的用户学习的其他课程
        relate_courses = Course.objects.filter(id__in=course_ids).order_by('-click_nums')[:5]

        # 获取课程资源
        all_resource = CourseResource.objects.filter(course=course)

        return render(request, 'course-video.html', {
            'course': course,
            'course_resource': all_resource,
            'relate_courses': relate_courses,
        })


class CommentsView(LoginRequiredMixin, View):
    """
    课程评论
    """
    def get(self, request, course_id):
        course = Course.objects.get(id=course_id)
        all_resource = CourseResource.objects.filter(course=course)
        all_comment = CourseConments.objects.all().order_by("-add_time")

        # 相关课程推荐
        user_courses = UserCourse.objects.filter(course=course)
        user_ids = [user_course.user.id for user_course in user_courses]
        all_user_courses = UserCourse.objects.filter(user_id__in=user_ids)
        # 取出所有课程 id
        course_ids = [user_course.course.id for user_course in all_user_courses]
        # 获取学过该课程的用户学习的其他课程
        relate_courses = Course.objects.filter(id__in=course_ids).order_by('-click_nums')[:5]

        return render(request, 'course-comment.html', {
            'course': course,
            'course_resource': all_resource,
            'relate_courses':relate_courses,
            'all_comment': all_comment
        })


class VideoPlayView(View):
    """
    视频播放
    """

    def get(self, request, video_id):
        video = Video.objects.get(id=video_id)
        course = video.lesson.course

        # 查询用户是否已经关联该课程
        user_courses = UserCourse.objects.filter(user=request.user, course=course)
        if not user_courses:
            user_course = UserCourse(user=request.user, course=course)
            user_course.save()

        # 相关课程推荐
        user_courses = UserCourse.objects.filter(course=course)
        user_ids = [user_course.user.id for user_course in user_courses]
        all_user_courses = UserCourse.objects.filter(user_id__in=user_ids)
        # 取出所有课程 id
        course_ids = [user_course.course.id for user_course in all_user_courses]
        # 获取学过该课程的用户学习的其他课程
        relate_courses = Course.objects.filter(id__in=course_ids).order_by('-click_nums')[:5]

        # 获取课程资源
        all_resource = CourseResource.objects.filter(course=course)

        return render(request, 'course-play.html', {
            'course': course,
            'course_resource': all_resource,
            'relate_courses': relate_courses,
            'video': video
        })


class AddCommentsView(View):
    """
    课程添加评论
    """
    def post(self, request):
        # 首先判断用户是否登录
        if not request.user.is_authenticated():
            return HttpResponse(json.dumps({'status': 'fail', 'msg': '用戶未登錄'}), content_type='application/json')

        course_id = int(request.POST.get('course_id', 0))
        comments = request.POST.get('comments', '')
        if course_id > 0 and comments:
            course_comments = CourseConments()
            course = Course.objects.get(id=course_id)
            course_comments.course = course
            course_comments.comments = comments
            course_comments.user = request.user
            course_comments.save()
            return HttpResponse(json.dumps({'status': 'success', 'msg': '评论添加成功'}), content_type='application/json')
        else:
            return HttpResponse(json.dumps({'status': 'fail', 'msg': '评论添加失败'}), content_type='application/json')

